The proposed study aims to determine whether there are differences in health measures particularly of cardio-metabolic risk(1) between children conceived by infertility treatment and children conceived naturally. Children conceived by infertility treatment include those born by assisted reproductive technologies (ART) and after non-ART treatments such as controlled ovarian hyperstimulation (COH) or ovulation induction (OI). The timing of puberty is also of interest, as some pubertal markers appear altered after IVF conception(2) and early adrenarche may confer additional CVD risks.(3) Treatment effects could arise either from the process of ovulation stimulation (which may be shared by both ART and non-ART treatments) or in vitro culture (which only occurs in ART). Epigenetics may be the mechanism underlying treatment effects.(4) Few studies have evaluated CVD risk factors among children/adolescence conceived by ART treatment and report conflicting findings.(5-10) None of these studies was conducted in the US and examinations varied. We propose therefore to continue the longitudinal follow-up of children (singletons and twins) from the Upstate New York Infant Development Screening Program (Upstate KIDS) from ages 6-8 years to fill in these data gaps. Specifically the study will: